Based on the tool developed by Rafols, Porter and Leydesdorff
Click on the "full screen" icon at the bottom right of the picture to access full features
Use the central wheel of the mouse to zoom in / out
Explore the graph by left-clicking and dragging around

The color of the nodes represent macro - disciplines (18 in total).
The size of the nodes represents the proportion of papers of neuroeconomics published in the journals of this particular field.
For example, for a graph on neuroeconomics: a large node size for "neurosciences" means that in 1999-2009, neuroeconomics was predominantly published in journals of neuroscience.